Mycelium cultivation, chemical composition and antitumour activity of a Tolypocladium sp. fungus isolated from wild Cordyceps sinensis

Abstract

Aims: To examine and illustrate the morphological characteristics and growth kinetics of Cs‐HK1, a Tolypocladium fungus, isolated from wild Cordyceps sinensis in solid and liquid cultures, and the major chemical constituents and antitumour effects of Cs‐HK1 mycelium. Methods and Results: The Cs‐HK1 fungus was isolated from the fruiting body of a wild C. sinensis and identified as a Tolypocladium sp. fungus. It grew rapidly at 22–25°C on a liquid medium containing glucose, yeast extract, peptone and major inorganic salts, with a specific growth rate of 1·1 day−1, reaching a cell density of 23·0 g dw l−1 in 7–9 days. Exopolysaccharides accumulated in the liquid culture to about 0·3 g l−1 glucose equivalent. In comparison with natural C. sinensis, the fungal mycelium had similar contents of protein (11·7–μg) and carbohydrate (654·6–μg) but much higher contents of polysaccharide (244·2 mg vs 129·5 mg), adenosine (1116·8–μg vs 264·6 μg) and cordycepin (65·7 μg vs 20·8 μg) (per gram dry weight). Cyclosporin A, an antibiotic commonly produced by Tolypocladium sp., was also detected from the mycelium extract. The hot water extract of mycelium showed low cytotoxic effect on B16 melanoma cells in culture (about 25% inhibition) but significant antitumour effect in animal tests, causing 50% inhibition of B16 cell‐induced tumour growth in mice. Conclusions: The Tolypocladium sp. fungus, Cs‐HK1, can be easily cultivated by liquid fermentation. The mycelium biomass contained the major bioactive compounds of C. sinensis, and the mycelium extract had significant antitumour activity. Significance and Impact of the Study: The Cs‐HK1 fungus may be a new and promising medicinal fungus and an effective and economical substitute of the wild C. sinensis for health care.

Maturational Alteration of Oppositely Orientated rDNA and Differential Proliferation of GC- and AT-biased Genotypes of Ophiocordyceps sinensis and Paecilomyces hepiali in Natural Cordyceps sinensis

“…and P. hepiali [17,21,24,25], Tolypocladium sp. and T. sinensis [2,21,23,26], and Pseudogymnoascus roseus [27]. Clustering analyses have indicated diversified phylogenetic patterns when different C. sinensis reference sequences were used for the analyses [2,3,19,22,23,[28][29][30].…”

Multicomponent Analysis of the Differential Induction of Secondary Metabolite Profiles in Fungal Endophytes

“…Previous studies on the morphology, growth kinetics, and main chemical components of solid or liquid cultures of Tolypocladium fungi isolated from wild Cordyceps sinensis, showed that the in vitro hyphae mycelium of Tolypocladium presented much higher contents of adenosine (1116.8 µg vs. 264.6 µg) than when the fungus was directly isolated from C. sinensis [18]. Similarly to what was observed for Tolypocladium, adenosine could represent a potential biomarker of the hyphae growth morphology state as observed in our strain.…”

A Comparative Study on Chemical Composition and Pharmacological Effects of <i>Paecilomyces hepiali</i> and Wild <i>Ophiocordyceps sinensis</i>

“…The mycelial protein content of P. hepiali (36.7%) obtained in this study is more than the mycelial protein contents reported by Ulziijard and Mau [14] for Sparassis crispa (32.61%), Inonotus obliquus (25.59%), Grifola frondosa (26.40%) and Anthrodia camphorata (9.49%). Leung et al [15] found slightly higher protein content in mycelium of a Tolypocladium sp. ).…”